Posted on 11/26/2008 4:23:55 AM PST by Halfmanhalfamazing
Where our line of sight hits the horizon is the distance from our boat to the horizon. A small boat first coming into view is assumed to be at that distance. In the picture above, the sailor cannot see the island's palm trees.
If an object, such as a large ship or a palm tree on an island, sticks up well above the water, we can see it from a further distance.
Here is how we can calculate how far we can see from a boat on the sea.
First let's assume that we are sitting in the cockpit of the boat and our eyes are 5 feet above the water and the seas are smooth. We can then look at the table below to see that we can see only 2.6 nautical miles to the horizon.
Now if we are looking at a palm tree on an island, we must determine how far the palm tree can see, or really how far someone on top of the palm tree can see. Let's assume the palm tree is 30 feet tall. Looking at the table, we can see the sight distance is 6.4 nm. To determine how far that palm tree is from our boat, when we first see it, we add our sight distance, 2.6 nm, to the "tree's sight distance", 6.4 nm, and find that we can see the palm tree from 9 nautical miles. This of course assumes no fog, rain, or other conditions that might obscure our view.
In case you were wondering about other heights, like when the deck of your boat is 4 feet over the water and your eye is another 4 feet over the deck, here is the calculation for finding sight distacne for any height.
Visible distance (in nm) = 1.17 x the square root of the height (in feet)
Try a few other combinations. For example, how far away could you be and see the first offshore oil rigs in the Gulf of Mexico?
Why this is important is because the oil drilling debate will be back, and it's an important thing to know.
Which means that an offshore oil drilling ban any further than somewhere around 25 miles is lunacy. Sure, higher height rigs would be visible around this distance, but you have to keep in mind the context. It would be a small black dot on the horizon.
This is hardly a problem for tourism.
Especially if these rigs are painted sea blue. Then you wouldn't see them at all.
Considering how eeeeeeeeeeeeeevil oil drilling has been tied to the global warming debate, knowing how far the human eye can see is a good thing to know when this comes back. At least I think.
Yeah, I know a few people who scuba dive and they all say the same thing about that; that these rigs make good artificial reefs after a while.
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From the bridge of a US Navy deystrouer you can see from 7-10 miles depending on swells
The perfect distance is where the oil is, not where you can’t see the oil rigs. If there was any “Constitutional Right to an unobstructed Scenic View” we should be tearing down those ugly skyscrapers and all the ugly billboards and business signage.
When I was in the upper penninsula back in July, we spent half a day sitting on a bluff at Grand Marais watching for ore carriers. We only saw one and it was little more than a speck on the horizon even with good binoculars.
The facts show how nonsensical and uninformed the public is about nonexistent environmental issues.
I doubt a single human being on Earth, other than oil workers, can see oil drilling on the Alaskan shelf.
Just madness, and I guarantee OPEC pays off our politicians.
^^^^^^^^^^^^^^The perfect distance is where the oil is, not where you cant see the oil rigs.^^^^^^^^^^^
That’s not necessarily true anymore with the invention of slant drilling.
^^^^^^^^^^^If there was any Constitutional Right to an unobstructed Scenic View we should be tearing down those ugly skyscrapers and all the ugly billboards and business signage.^^^^^^^^^^^
Agreed.
However, I’m sure we could all agree on a reasonable expectation. I actually would think it’d be kind of cool if some beaches had rigs right there that you could see. But I marvel at all things. Human inventions such as skyscrapers, bridges, and earthmovers are fantastic. So are big trees, waterfalls, and things you see out in nature. I’d love to go see a rainforest one day.
But others aren’t like me who can see something good in just about everything.
Even the Kennedys pushed wind away from their shores because they were eyesores.
But with everything said, I’m sure you can agree with me that this is important to know. I’m surprised someone else hasn’t tied these two together.
^^^^^^^^^^^^^^^^^^The facts show how nonsensical and uninformed the public is about nonexistent environmental issues.^^^^^^^^^^^^^^^
Which is why I hope in the coming minutes, hours, and days you’ll be emailing this information to as many people as you can.
:-)
You know as well as I do that the media isn’t gonna educate them. So it’s up to us.
Nope. And, once he is inaugurated, the price will start to skyrocket again and, this time, it will hit astronomical levels. Whoever is manipulating the oil market knows that the Obamessiah will do nothing towards American energy independence.
IMO, whoever is manipulating the oil market (and the economy) is also manipulting Obama...He is a puppet on strings....
Thanks!
The spill issue with regard to off-shore drilling is another ruse, yet ...
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